The literature of this period belongs to the second half of the 5th Century AH/11th Century AD until the beginning of the 7th Century AH/13th Century AD. In this period, besides being a natural continuation of the poetry of the previous period, Persian poetry passed through a period of evolution and perfection and the Persian language and Dari literature crossed beyond the local boundaries. The first and foremost factor in the spread of the Persian language outside the boundaries of Iran was the expansionist policy of Nāser al-Din Saboktagin and Soltān Mahmud Ghaznavi towards India. Following the reign of the Ghaznavids, as a result of the penetration of the Seljuqs in Asia Minor, the Persian language came to spread in that region and became the official language. Therefore, towards the end of this period and the beginning of the 7th Century AH, Asia Minor became one of the important centers of Dari Persian.Poetry: The geographical spread of the poets of the Seljuq and Khwārazmshāhi period brought about the emergence of three styles of poetry in Iran.A. The Style of the Poets of Khorāsān: This group of poets were inclined towards the revival and perfection of the Sāmānid style of poetry as well as the poetry of the early Ghaznavid period to the extent that Nāser Khosrow and Qatrān adhered to the Sāmānid style of poetry. Nevertheless, with the introduction of theological-philosophical issues in poetry, Nāser Khosrow, and with the introduction of figurative language, Qatrān, introduced a new wave in the Khorāsāni style. On the other hand, Lāme’i is the typical example of the poets who followed the style of the early Ghaznavid period, while other poets of this period like Mas’ud Sa’d introduced a new style that was a combination of the separate styles followed by Farrokhi and Onsori. In continuation of this style, a new order of poets began to emerge in the second part of the 6th century AH/12th century AD, the most prominent of which was Anvari. Keeping in view the colloquial language of the day, this group of poets composed simple and fluid poems which mainly resembled general conversation; and since the masses used simple Arabic expressions in their day-to-day interactions their language of poetry became intermingled with simple Arabic expressions. The main difference between the poetry of this period and that of the early Ghaznavid period was that some kinds of the works of this period (like the odes) came to evolved into a more complex style owing to two main reasons. The first reason was that Anvari and his followers were inclined to the composition of subtle poetry with cryptic meanings, and secondly, the contemporary group of poets employed scientific thought as well as terms and phrases of various fields of knowledge in their works.B. The Style of the Poets of Āzarbāyjān: Alongside the modifications that Anvari and his followers brought into Persian poetry in Khorāsān, and with the establishment of the Irāqi style of poetry, a certain group of poets created a completely new style of poetry in the northwest of Iran that came to be known as the Āzarbāyjāni style. The most important poets of this period include Abu al-Alā Ganjeh’i, Falaki Shervāni, Mojir al-Din, Bilqāni, Khāqāni, and Nezāmi. This style of poetry has also occasionally been referred to as the “Arrāni” style. The difference between the poetry styles of the poets of Āzarbāyjān and Khorāsān has been attributed to the following three factors:i. The poets of Āzarbāyjān laid the foundation for their new style of composition following the changes that Anvari and Sanā’i brought about in the poetry of the Khorāsān poets;ii. The access to the new style of the Irāqi poets had made it easier for the Āzarbāyjāni poets to distance themselves from the Khorāsāni style; and iii. Cultural differences, proximity with the non-Iranian communities, and the influence that the Āzari and other Iranian dialects on the Persian language of the Āzarbāyjān region – that had intermingled with the Arabic language since a long time – had resulted in the emergence of a mood that was very different from the one that prevailed among the Khorāsāni poets.C. The Style of the Poets of Iraq: This style of poetry refers to the one adopted by the poets of Esfahān, Hamadān, Rey, and the regions neighboring these cities. The most outstanding poet of this style of poetry was Jamāl al-Din Esfahāni who played a crucial role in the evolution and perfection of the “ghazal” during his times.The most important feature of the poetry of this period is the inclination of a group of poets towards the composition of ghazals as well as Gnostic (irfāni) subjects. Indications pointing towards an inclination towards irfān can be found even in the works of the poets of the previous period. However, the 6th Century AH/12th Century AD marks the flowering of Gnostic literature. The influence of Gnostic thought and views on the literature of this period resulted in the emergence of two simultaneous trends in the literary ambience of those times. Firstly, it resulted in introducing a fresh trend in the contents of Persian poetry and it, secondly, led to a distancing of the poets from the royal courts.For the first time during this period, Sanā’i Ghaznavi embarked upon the composition of great Gnostic poems and left as legacies such mathnavis as the “Hadiqah al-Haqiqah” and the “Tariq al-Tahqiq”. After him, Attār Neishāburi composed numerous works in the field of tasawwuf, from among which reference can be made to the “Manteq al-Tayr” (The Conversation of the Birds), the “Asrārnāmeh” (The Book of Secrets), the “Mosibatnāmeh” (The Book of Strife), and the “Elāhināmeh” (The Book of Divine Secrets).The ghazal form of poetry – which gained a special significance in this period – came to more or less be employed in Persian poetry since the 4th Century AH/10th Century AD. However, Anvari and his followers established a new style of poetry and presented subtle subjects in simple and fluid words in the form of fine ghazals, and in this manner, paved the path for the emergence of the great ghazal poets of the following period.In comparison with the earlier periods, the Seljuq and Khwārazmshāhi Era marked a decline in the field of epic poetry since, on the one hand, Ferdowsi, who was the great epic poet of the previous period, had spared no effort in presenting the Iranian history and national legends in the form of poetry by composing the “Shāhnāmeh” while, on the other hand, as some scholars have pointed out the old trend and language of epic writing was not compatible with the existing trends of this period. More importantly, since the slaves and the yellow-raced tribes had come into power and since religious fanaticism had gained strength in this period, the nationalistic spirit had been dampened and it was, thus, no longer apt for the poets to compose nationalistic epic poetry. Nevertheless, in the early years of this period, i.e. in the second half of the 5th Century AH/11th Century AD, certain poets engaged themselves in completing the path taken on by Ferdowsi. For instance, Asadi Tusi composed the “Garshāspnāmeh”, Irānshāh bin Abi al-Khayr composed the “Bahman-nāmeh” and the “Kushnāmeh” while Atā’i Rāzi composed the “Borzunāmeh”.During this same period, while the composition of nationalist and heroic epics was facing decline, a trend of story-writing or as some scholars have referred to it, the trend of composing “romantic epics” gained favor. The foremost established story-writer who introduced a new style in the mid-5th Century AH/11th Century AD was Fakhr al-Din As’ad Gorgāni. With his translation of “Vays va Rāmin” from the Pahlavi language into Dari Persian poetry, he established a new school in the field of story-writing that came to be emulated by many other poets in times to follow. It was Nizāmi Ganjavi who took the art of story-writing to its zenith towards the end of the 6th Century AH/11th Century AD. Nizāmi’s skilful composition of the various stories included in his book, the “Panj Ganj”, inspired many Persian-speaking poets to follow his style of poetry for centuries to come.The greatest phenomenon of the poetry of this period, however, was the emergence of Omar Khayyām Neishāburi who had established his own special style in the field of Persian literature. It was Khayyām, who had for the first time, presented the world with deep philosophical thoughts in the form of eloquent quatrains (rubāiyāt) clad in subtlety, wit, and asceticism.The attention paid by the poets of this period towards subtlety and the competition shared among them as well as their command over literary skills and other fields of knowledge resulted in Persian poetry acquiring a proficient and technically expressive form. On the other hand, the poets were challenged to employ intricate radifs and poetic skills. On the whole, the 6th Century AH or in other words, the Seljuq period is the most significant period in the area of Iranian literature from the historical and classificatory viewpoints. A variety of styles in prose and poetry existed side by side during this period and in the area of poetry, the prose poem style as well as the “Arrāni” style (of the poets of Āzarbāyjān) pushed aside the simpler Khorāsāni style of poetry.Prose: The 5th Century AH/11th Century AD marked the beginning of the proximity between Khorāsān and Baghdād and the onset of the influence of the Arabic language in Persian prose. Through the course of this period, the Seljuqs, too, encouraged the growth of the Arabic language in Iran owing to their commitment towards the spread of Islam. Nevertheless, following his ascension to the throne, Ālb-Arslān ordered for all the royal registers to be written in Persian which resulted in the creation of a variety of works in Persian prose. The first and foremost example of the style of prose writing of this period is Abu al-Fazl Beyhaqi’s work, the “Tārikh-e Beyhaqi” in the compilation of which he has resorted to great detail and the repetitive employment of synonyms and phrases for the sake of elucidation. However, the writers who followed him, and especially Nasrollāh Monshi, the author of “Kalilah va Demnah”, and Qāzi Hamid al-Din Balkhi, the author of the “Maqāmāt Hamidi” which resulted in the emergence of a very figurative and technical style of writing in the 6th Century AH/12th Century AD.One of the branches of the Persian prose of this period comprised Sufi writings. The Gnostics of the 5th Century AH wrote in simple words, from among whose works, mention can be made of the “Kashf al-Mahjub” of Hujwiri and also the “Tazkirah al-Awliyā” of Attār Neishāburi that has been written in a “morsal” style (ending with a moral advice). The evolution of the Sufi writings in the form of an inclination towards a rhythmic prose style came about under the influence of Arabic literature and, apparently, it was Khwājeh Abdollāh Ansāri who had first resorted to this style of rhythmic prose in such of his works as the “Monājātnāmeh” and the “Kanz al-Sālekin” towards the end of the 5th Century AH/11th Century AD. The prose works of this period are great in number and subject variety but the dominant style of the prose-writing of this period was technical even though a style that fell somewhere between the technical and “morsal” styles of prose was also in use.